1. Field of the Invention
The present invention relates to a metal catalyst composition for producing furfural derivatives from raw materials of lignocellulosic biomass, and method for producing furfural derivatives using the composition. More particularly to the composition and the method which may turn lignocellulosic biomass raw materials to furfural derivatives through single step process without additional saccharification process by using various kinds of metal catalyst in optimal reacting condition, thus significantly reducing process costs, unlike conventional composition and method going through multi step process.
2. Description of the Related Art
Continuous reduction in limited oil resources and dramatic increase in oil demand due to the rapid growth of emerging countries like the BRICs cause the imbalance between demand and supply of oil, which leads to the era of high oil prices. Large amount of green house gases are emitted irreversibly due to reckless use of non-cyclic oil resources, and thus cause a serious environment problem like global warming. Because of those circumstances, most of countries come up with tough regulation of imposing costs on the amount of emitted green house gases to pose tough sanctions on the use of the non-cyclic oil resources.
Advanced countries are already taking great efforts to replace the oil resources with renewable and sustainable resources like biomass. For those efforts they are industrially producing biofuels such as bioethanol, biodiesel, and biomass-derived chemical materials such as lactic acid and propanediol which are raw materials for polymer elements.
However, the industrially produced biomass derived fuels and raw materials in current times use crop biomass resources such as glucide group (sugar cane, sugar beet, etc) and starchy group (corn, potato, sweet potato, etc) which are used for food as supply sources. This leads to a drop in agricultural lands, a rise in grain prices and current controversy about global food problem in the international community.
In order to solve those problems, attentions are drawn to plants that grow naturally with great vitality on non-cultivated lands, crop residue after cultivation and carbohydrates such as celluloses and hemicelluloses that can be extracted from lignocellulosic biomasses such as waste lignocellulosic resources, etc. The cellulose and hemicelluloses are regarded as replaceable by carbohydrates sucroses or starches coming from starchy group.
The extractable carbohydrate polymers celluloses and hemicelluloses from lignocellulosic biomass are produced in large amounts (production volume: 127 billion ton per year) every year through photosynthesis, and only 3-4% of the production volume is currently used. Due to the reason, advanced countries such as the U.S., Europe, Japan, etc are actively carrying out research on utilizing celluloses and hemicelluloses produced from lignocellulosic biomass. The carbohydrate polymers produced from lignocellulosic biomass are polysaccharides whose hexose or pentose structure is connected 1 or 2-dimmentionally. Normally the polysaccharides turn to hexose glucoseor or hexose fructose, and pentose xylose through hydrolysis saccharification process, and then they are applied to the next organism fermentation or catalyst chemical processes through separation and purification process. Specifically, commonly used production method for obtaining the final target compound from lignocellulosic biomass raw materials comprises; a pre-process (a) for extracting polysaccharides carbohydrate polymers from biomass supply source; a saccharification process (b) for obtaining hexose glucose or hexose fructose and pentose xylose; and a separation and purification process (c) of produced monosaccharide compound; and a organism fermentation or catalyst chemical multi-stage process (d) for obtaining final compound. However, the multi-stage processes cause an increase in production costs and a decreased in yield.
The furfural derivatives compound from biomass is currently drawing a lot of attention. The hexose derived 5-hydroxymethyl-2-furfural and pentose derived 2-furfural are typical core platforms and are widely applicable for next generation biofuels, bio-based plastics monomer and adhesives, and eco-friendly adhesives and coating agents fine chemistry products. A research on mass production methods of those products is being actively carried out.
[A Structural Formular of 2-Hydroxy-Methyl Furfural]
[A Structural Formular of 2-Furfural]

The typical technology for producing HMF from derived carbohydrates from biomass has a method for obtaining HMF in acid catalyst condition thorough dehydration reaction with fructose that serves as a starting material. This method has an advantage of easily obtaining furan structure without additional isomerization reaction unlike pentose fructose and hexose sugar compounds. Dumesic's group at the University of Wisconsin-Madison reported on a technology for producing HMF under various solvent conditions through acid catalyst conversion reaction with fructose that serves as a starting material (Science, 2006, 312, 1933-1937). According to the report, the technology showed high process efficiency by obtaining high HMF concentration (30 wt %).
However, for fructose, it has limited supply source as the starting material and exists only in agricultural productions. In the technology above, the solvents with optimum performance has the high boiling point, and thus high-energy distillation process is required to eliminate the boiling point, which requires new separation process technology.
Besides, a saccharification process for effectively obtaining glucose from polysaccharide cellulose is required and this is the problem for the fructose.
Meanwhile, 2-furfural is usable itself as a fuel material. Furfuryl alcohol and furfuryl acid derivatives from oxidation-reduction process are compounds that are used as polymer elements raw materials and are obtained through dehydration reaction under the acid condition of hemicellulose existed in lignocellulosic biomass. However, the performing condition of the dehydration reaction through sulfuric acid and strong acid is poor and cause a huge amount of waste acid and waste water.
So, developing a method for simply manufacturing furfural derivatives without complex and high-cost pre-process and saccharification process is required.